A simple trick to improve your memory

Want to enhance your memory for facts? Tom Stafford explains a counterintuitive method for retaining information.

If I asked you to sit down and remember a list of phone numbers or a series of facts, how would you go about it? There’s a fair chance that you’d be doing it wrong.

One of the interesting things about the mind is that even though we all have one, we don’t have perfect insight into how to get the best from it. This is in part because of flaws in our ability to think about our own thinking, which is called metacognition. Studying this self-reflective thought process reveals that the human species has mental blind spots.

One area where these blind spots are particularly large is learning. We’re actually surprisingly bad at having insight into how we learn best.

Researchers Jeffrey Karpicke and Henry Roediger III set out to look at one aspect: how testing can consolidate our memory of facts. In their experiment they asked college students to learn pairs of Swahili and English words. So, for example, they had to learn that if they were given the Swahili word ‘mashua’ the correct response was ‘boat’. They could have used the sort of facts you might get on a high-school quiz (e.g. “Who wrote the first computer programs?”/”Ada Lovelace”), but the use of Swahili meant that there was little chance their participants could use any background knowledge to help them learn. After the pairs had all been learnt, there would be a final test a week later.

Now if many of us were revising this list we might study the list, test ourselves and then repeat this cycle, dropping items we got right. This makes studying (and testing) quicker and allows us to focus our effort on the things we haven’t yet learnt. It’s a plan that seems to make perfect sense, but it’s a plan that is disastrous if we really want to learn properly.

Karpicke and Roediger asked students to prepare for a test in various ways, and compared their success – for example, one group kept testing themselves on all items without dropping what they were getting right, while another group stopped testing themselves on their correct answers.

On the final exam differences between the groups were dramatic. While dropping items from study didn’t have much of an effect, the people who dropped items from testing performed relatively poorly: they could only remember about 35% of the word pairs, compared to 80% for people who kept testing items after they had learnt them.

It seems the effective way to learn is to practice retrieving items from memory, not trying to cement them in there by further study. Moreover, dropping items entirely from your revision, which is the advice given by many study guides, is wrong. You can stop studying them if you’ve learnt them, but you should keep testing what you’ve learnt if you want to remember them at the time of the final exam.

Finally, the researchers had the neat idea of asking their participants how well they would remember what they had learnt. All groups guessed at about 50%. This was a large overestimate for those who dropped items from test (and an underestimate from those who kept testing learnt items).

So it seems that we have a metacognitive blind spot for which revision strategies will work best. Making this a situation where we need to be guided by the evidence, and not our instinct. But the evidence has a moral for teachers as well: there’s more to testing than finding out what students know – tests can also help us remember.

Read more: Why cramming for tests often fails

This is my BBC Future column from last week. The original is here

Happy Birthday Tetris!

Released on 6th of June 1984, Tetris is 30 years old today. Here’s a video where I try and explain something of the psychology of Tetris:

All credit for the graphics to Andrew Twist. What I say in the video is based on an article I wrote a while back for BBC Future.

As well as hijacking the minds and twitchy fingers of puzzle-gamers for 30 years, Tetris has also been involved in some important psychological research.

My favourite is Kirsh and Maglio’s work on “epistemic action“, which showed how Tetris players prefer to rotate the blocks in the game world rather than mentally. This using the world in synchrony with your mental representations is part of what makes it so immersive, I argue.

Other research has looked at whether Tetris’s hook on our visual imagery can be used to help people with PTSD flashbacks.

And don’t forget that Tetris was the control condition is Green and Bavelier’s now famous studies of how action video games can train visual attention

In my own research I’ve used simple games to explore skill learning. John Lindstedt and Wayne Gray at Rensselaer Polytechnic Institute have been pursuing a parallel line looking at expertise in Tetris players.

I’m sure there are more examples, if you know of any researching using Tetris let me know. Happy Birthday Tetris!

The day video games ate my school child

The BBC is reporting that a UK teachers union “is calling for urgent action over the impact of modern technology on children’s ability to learn” and that “some pupils were unable to concentrate or socialise properly” due to what they perceive as ‘over-use’ of digital technology.

Due to evidence reviewed by neuroscientist Kathryn Mills in a recent paper (pdf) we know that we’ve really got no reason to worry about technology having an adverse effects on kids’ brains.

It may not be that the teachers’ union is completely mistaken, however. They may be on to something but maybe just not what they think they’re onto.

To make sense of the confusion, you need to check out an elegant study completed by psychologists Robert Weis and Brittany Cerankosky who decided to test the psychological effects of giving young boys video game consoles.

They asked for families to take part who did not have a video-game system already in their home, had a parent interested in purchasing a system for their use, and where the kid had no history of developmental, behavioural, medical, or learning problems.

They ran a randomised controlled trial or RCT where 6 to 9-year-old boys were first given neuropsychological tests to measure their cognitive abilities (memory, concentration and problem-solving) and then randomly assigned to get a video games console.

The families in the control group were promised a console at the end of the study, by the way, so they didn’t think ‘oh sod it’ and go and buy one anyway.

So, we have half the kids with spanking brand new console, and, as part of the trial, the amount of time kids spent gaming and doing their school work was measured throughout, as was reporting of any behavioural problems. At the end of the study their academic progress was measured and their cognitive abilities were tested again.

The results were clear: kids who got video game consoles were worse off academically compared to their non-console-owning peers – their progress in reading and writing had suffered.

But this wasn’t due to an impact on their concentration, memory, problem-solving or behaviour – their neuropsychological and social performance was completely unaffected.

By looking at how much time the kids spent on the consoles, they found that reduced academic performance was due to the fact that kids in the console-owning families started spending less time doing their homework.

In other words, if your kids play a lot of computer games instead of doing homework they may well appear worse off, and from the teachers’ point-of-view, might seem a little slowed-down compared to their peers, but this is not due to cognitive changes.

Interestingly, teachers may not be in the best position to see this distinction very well because they tend, like the rest of us, to measure ability by performance in the tasks they set and not in comparison to neuropsychological test performance.

The solution is not to panic about technology as this same conclusion probably applies to anything that displaces homework (too many piano lessons will have the same effect) but good parental management of out-of-school time is clearly important.

Link to locked study on the effects of video games.

noob 2 l33t: now with graphs

Myself and Mike Dewar have just had a paper published in the journal Psychological Science. In it we present an analysis of what affects how fast people learn, using data from over 850,000 people who played an online game called Axon (designed by our friends Preloaded. This is from the abstract:

In the present study, we analyzed data from a very large sample (N = 854,064) of players of an online game involving rapid perception, decision making, and motor responding. Use of game data allowed us to connect, for the first time, rich details of training history with measures of performance from participants engaged for a sustained amount of time in effortful practice. We showed that lawful relations exist between practice amount and subsequent performance, and between practice spacing and subsequent performance. Our methodology allowed an in situ confirmation of results long established in the experimental literature on skill acquisition. Additionally, we showed that greater initial variation in performance is linked to higher subsequent performance, a result we link to the exploration/exploitation trade-off from the computational framework of reinforcement learning.

The paper is behind a paywall for the next year, unfortunately, but you can find a pre-print, as well as all the raw data and analysis code (written in Python) in the github repo. I wrote something on my academic blog about the methods and why we wanted to make this an example of open science.

Links: The paper: Tracing the Trajectory of Skill Learning With a Very Large Sample of Online Game Players
And the data & code.

Thanks to @phooky for suggesting an alternative title for the paper, which I’ve used to title this post

BBC Future column: Personal superstitions

I’m writing a fortnightly column for BBC Future, about everyday brain quirks (as I’ve mentioned previously). My marvellous editor has told me I can repost the columns here, with a three day delay. There’s a bit of a backlog, including Why can smells unlock memories?, Why you’re bad at names and good at faces, and Why we need to sleep?, but you’ll have to visit the site for them. The column from a month ago was on personal superstitions. And without further ado, here it is:

Legendary Dutch footballer Johan Cruyff used to slap his goalkeeper in the stomach before each match. Tennis ace Serena Williams always bounces her ball five times before her first serve. Jennifer Aniston, it is reported, touches the outside of any plane she flies in with her right foot before boarding.

From touching wood for good luck, to walking around ladders to avoid bad luck, we all have little routines or superstitions, which make little sense when you stop to think about them. And they are not always done to bring us luck. I wait until just after the kettle has boiled to pour the water for a cup of tea, rather than pouring just before it boils. I do not know why I feel the need to do this, I am sure it cannot make a difference to the drink.

So, why do I and others repeat these curious habits? Behind the seemingly irrational acts of kettle boiling, ball bouncing or stomach slapping lies something that tells us about what makes animals succeed in their continuing evolutionary struggles.

Repeat behaviour

We refer to something that we do without thinking as being a habit. This is precisely why habits are useful – they do not take up mental effort. Our brains have mechanisms for acquiring new routines, and part of what makes us, and other creatures successful is the ability to create these habits.

Even pigeons can develop superstitious habits, as psychologist B. F. Skinner famously showed in an experiment. Skinner would begin a lecture by placing a pigeon in a cage with an automatic feeder that delivered a food pellet every 15 seconds. At the start of the lecture Skinner would let the audience observe the ordinary, passive behaviour of the pigeon, before covering the box. After fifty minutes he would uncover the box and show that different pigeons developed different behaviours. One bird would be turning counter clockwise three times before looking in the food basket, another would be thrusting its head into the top left corner. In other words, all pigeons struck upon some particular ritual that they would do over and over again.

Skinner’s explanation for this strange behaviour is as straightforward as it is ingenious. Although we know the food is delivered regardless of the pigeon’s behaviour, the pigeon doesn’t know this. So imagine yourself in the position of the pigeon; your brain knows very little about the world of men, or cages, or automatic food dispensers. You strut around your cage for a while, you decide to turn counter clockwise three times, and right at that moment some food appears. What should you do to make that happen again? The obvious answer is that you should repeat what you have just been doing. You repeat that action and – lo! – it works, food arrives.

From this seed, argued Skinner, superstition develops. Superstitions take over behaviour because our brains try and repeat whatever actions precede success, even if we cannot see how they have had their influence. Faced with the choice of figuring out how the world works and calculating the best outcome (which is the sensible rational thing to do), or repeating whatever you did last time before something good happened, we are far more likely to choose the latter. Or to put it another way: “if it ain’t broke, don’t fix it”, regardless of the cause.

Habit forming

University of Cambridge psychologist Tony Dickinson has taken the investigation of habits one step further. Dickinson trains rats to press a lever for food and perform another action (usually pulling a chain) for water. The animals can now decide which reward they would like most. If you give them water before the experiment they press the lever for food, if you give them food beforehand they pull the chain for water.

But something strange happens if the animals keep practising these actions beyond the point at which they have effectively learnt them – they seem to “forget” about the specific effects of each action. After this “overtraining”, you feed the animal food before the experiment and they keep on pressing the lever to produce food, regardless of the fact that they have just been fed. The rat has developed a habit, something it does just because it the opportunity is there, without thinking about the outcome.

Sound like anyone we know? To a psychologist, lots of human rituals look a lot like the automatic behaviours developed by Skinner’s pigeons or Dickinson’s rats. Chunks of behaviour that do not truly have an effect on the world, but which get stuck in our repertoire of actions.

And when the stakes are high – such as with sports – there is even more pressure on our brains to “capture” whatever behaviours might be important for success. Some rituals can help a sportsperson to relax and get “in the zone” as part of a well-established routine before and during a big game. But some of the habits you see put my kettle boiling routine to shame. Tiger Woods always wears red the last day of a golf tournament, because he says it is his “power colour”. In baseball, Wade Boggs claimed he hit better if he ate chicken the night before. Soccer’s Kolo Toure once missed the start of the second half because refused to come out – superstition dictated he had to be the last player to re-emerge from the dressing room, but on that occasion he was stuck there waiting for a stricken teammate to finish treatment.

We cling to these habits because we – or ancient animal parts of our brains – do not want to risk finding out what happens if we change. The rituals survive despite seeming irrational because they are coded in parts of our brains, which are designed by evolution not to think about reasons. They just repeat what seemed to work last time. This explains why having personal rituals is a normal part of being human. It is part of our inheritance as intelligent animals, a strategy that works in the long-term, even though it clearly does not make sense for every individual act.

Link: My columns at BBC Future
Link: UK readers – you’ll have to try it via here

Make study more effective, the easy way

Decades old research into how memory works should have revolutionised University teaching. It didn’t.

If you’re a student, what I’m about to tell you will let you change how you study so that it is more effective, more enjoyable and easier. If you work at a University, you – like me – should hang your head in shame that we’ve known this for decades but still teach the way we do.

There’s a dangerous idea in education that students are receptacles, and teachers are responsible for providing content that fills them up. This model encourages us to test students by the amount of content they can regurgitate, to focus overly on statements rather than skills in assessment and on syllabuses rather than values in teaching. It also encourages us to believe that we should try and learn things by trying to remember them. Sounds plausible, perhaps, but there’s a problem. Research into the psychology of memory shows that intention to remember is a very minor factor in whether you remember something or not. Far more important than whether you want to remember something is how you think about the material when you encounter it.

A classic experiment by Hyde and Jenkins (1973) illustrates this. These researchers gave participants lists of words, which they later tested recall of, as their memory items. To affect their thinking about the words, half the participants were told to rate the pleasantness of each word, and half were told to check if the word contained the letters ‘e’ or ‘g’. This manipulation was designed to affect ‘depth of processing’. The participants in the rating-pleasantness condition had to think about what the word meant, and relate it to themselves (how they felt about it) – “deep processing”. Participants in the letter-checking condition just had to look at the shape of the letters, they didn’t even have to read the word if they didn’t want to – “shallow processing”. The second, independent, manipulation concerned whether participants knew that they would be tested later on the words. Half of each group were told this – the “intentional learning” condition – and half weren’t told, the test would come as a surprise – the “incidental learning” condition.

I’ve made a graph so you can see the effects of these two manipulations

As you can see, there isn’t much difference between the intentional and incidental learning conditions. Whether or not a participant wanted to remember the words didn’t affect how many words they remembered. Instead, the major effect is due to how participants thought about the words when they encountered them. Participants who thought deeply about the words remembered nearly twice as many as participants who only thought shallowly about the words, regardless of whether they intended to remember them or not.

The implications for how we teach and learn should be clear. Wanting to remember, or telling people to remember, isn’t effective. If you want to remember something you need to think about it deeply. This means you need to think about what you are trying to remember means, both in relationship to other material you are trying to learn, and to yourself. Other research in memory has shown the importance of schema – memory patterns and structures – for recall. As teachers, we try and organise our course material for the convenience of students, to best help them understand it. Unfortunately, this organisation – the schema – for the material then becomes part of the assessment and something which students try to remember. What this research suggests is that, merely in terms of remembering, it would be more effective for students to come up with their own organisation for course material.

If you are a student the implication of this study and those like it is clear : don’t stress yourself with revision where you read and re-read textbooks and course notes. You’ll remember better (and understand much better) if you try and re-organise the material you’ve been given in your own way.

If you are a teacher, like me, then this research raises some disturbing questions. At a University the main form of teaching we do is the lecture, which puts the student in a passive role and, essentially, asks them to “remember this” – an instruction we know to be ineffective. Instead, we should be thinking hard, always, about how to create teaching experiences in which students are more active, and about creating courses in which students are permitted and encouraged to come up with their own organisation of material, rather than just forced to regurgitate ours.

Reference: Hyde, T. S., & Jenkins, J. J. (1973). Recall for words as a function of semantic, graphic, and syntactic orienting tasks. Journal of Verbal Learning and Verbal Behavior, 12(5), 471–480.

Now available in Italian Insegnare ed apprendere in modo efficace (thanks Giuliana!)

The death of the mind

Business Week has an important article on how internet companies are using the massive data sets collected from the minutia of users’ behaviour to influence customer choices.

The article is a useful insight into how tech companies are basing their entire profit model on the ability to model and manipulate human behaviour but the implication for psychology is, perhaps, more profound.

Psychological theories and ideas about how the mind work seem to play a small, if not absent role in these models which are almost entirely based on deriving mathematical models from massive data sets.

Sometimes the objective is simply to turn people on. Zynga, the maker of popular Facebook games such as CityVille and FarmVille, collects 60 billion data points per day—how long people play games, when they play them, what they’re buying, and so forth. The Wants (Zynga’s term is “data ninjas”) troll this information to figure out which people like to visit their friends’ farms and cities, the most popular items people buy, and how often people send notes to their friends.

Discovery: People enjoy the games more if they receive gifts from their friends, such as the virtual wood and nails needed to build a digital barn. As for the poor folks without many friends who aren’t having as much fun, the Wants came up with a solution. “We made it easier for those players to find the parts elsewhere in the game, so they relied less on receiving the items as gifts,” says Ken Rudin, Zynga’s vice-president for analytics.

Although the example given might seem trivial, it is a massive generator of profit and can be applied to any sort of online behaviour.

What’s striking is that the relationships between the context, motivations, evaluation and behaviour of the users is not being described in terms of how the mind or brain understand and respond the situation but purely as a statistical relationship.

It is psychology devoid of psychology. Rather than the wisdom of crowds approach, it’s the behaviour of zombies model. Unsurprisingly, none of the entrepreneurs mentioned are cognitive scientists. They’re all mathematicians.

I am reminded of the Wired article ‘The End of Theory’ which warned that big data crunching computers could solve scientific problems in the same way. The generated mathematical model ‘works’ but the model is uninterpretable and does not help us understand anything about what’s being studied.

Similarly, while the experimental psychologist’s dream for more than a century has been to work with large data sets to have confidence in our conclusions about the mind, the reality, currently being realised, may actually make the mind redundant in the majority of the commercial world.

Link to Business Week article (via @ivanoransky).